ISO 27427:2013 specifies requirements for the safety and performance testing of general purpose nebulizing systems intended for continuous or breath-actuated delivery of liquids, in aerosol form, to humans through the respiratory system. ISO 27427:2013 includes gas-powered nebulizers which can be powered by, e.g., compressors, pipeline systems, cylinders, etc., and electrically powered nebulizers [e.g., spinning disc, ultrasonic, vibrating mesh (active and passive), and capillary devices] or manually powered nebulizers.